Terminal for electric cables



Nov. 2 1926.

A. B. SAURMAN TERMINAL FOR ELECTRIC CABLES Filed Dec. 17, 1924 2 Sheets-Sheet` 1- FIELI- P. 4, u Nm. m M 65 6, v Nw l 5 w 0.... 1 w. Num Aww www.. UmlE MEWE .MDI BFwF A Amm MF .M R E T n. 6. 2. 9 1... 6 2 w W N F Patented Newz, 1926.

Armen n. sAUnMAN, or PITTSBURGH, rnNNsvnvANr,assrenonrosrnnnann UN- DERGROUND CABLE COMPANY, TION OF PENNSYLVANIA.

Application led December 17, 1924. l Seriali-No..

My invention relates to improvements in terminals for electric cables, and consists 1n a modification of structure, in consequence of which it becomes possible to vfill the spaces within the terminal casing more expeditiously and more completely than hitherto has been possible. In consequence, I `overcome defects and difficulties consequent upon faults of installation which in existing practice are of not infrequent occurrence.

I have worked my invention out in connection with a terminal of the particular construction shown and described in United States Letters Patent No. 1,159,655, granted November 9, 1915, on theapplication of Charles W. Davis, and, while it is not lim'- ited in adaptability to that construction alone, I shall here show and describe it so adapted. v

In the accompanying drawings Fig. I is a view partly in side elevation, partly'in longitudinal section, of a terminal in the construction of which my invention is .embodied; Fig. II is a view in detail and to larger scale, on the same plane of sectionas that lemployed in Fig. I; and Fig. III is 'a view in transverse section, on the plane indicated at III-#IIL Fig. II, ota certain member of the structure there shown. .f

The terminal, as it is shown in Fig. I, includes a two-part thimble, consisting of a cable-receiving bell 1 and a lead-receiving fork 2. The bell 1 is adapted to be secured, as shown, by a wiped-solder jointto the cable-sheath instance with three sleeve-like projections 3. Thus the particular structure of the figure is one which is adapted to serveas the ter-V Y minal for a three-conductor cable. The? thimble parts may be suitably united, as by the screw-thread union shown. ,e

A sleeve 4 of insulatin material, ordi- 'narily porcelain, is securein each sleevelike pro'ection 3. The union is preferably effected y means of an exteriorly threaded ring of metal 5 permanently sleeve 4 and engaging a corresponding interiorly screw-threaded 'surface atl the edge lofprojection 3. lThe sleeve 4 is exteriorly, "as indicated at 6, 7.' "Thefopen- `pole-piece for an aerial the fork 2 is provided in this attached to petticoated 0F PITTSBURGH, PENNSYLYANIA, .CORPORA- TERMINAL ron Ennornro canins.,

ing` through v leeve 4,1the borethrough the' sleeve, is stepped, at 9.

A conductingstem llextends within the bore of sleeve 4. This vstem isat its inner end so shaped as to be brought into electrical union with a Abared` cable conductor 13. Fig. II shows it to be socketed, at 33. At its outer end the stem is screw-threaded, and at an intermediate point in its length it is provided externally with a shoulder, adapt- 60 i' ed in assembly to engage the step` 9 of the Y bore of thesleeve. Threenuts, 14, 34, and 18 are successively applicable lto the outer screw-threaded 'end of stem 11. The

outermost nut 18 is preferably a cap-nut. 65

'One' at least of the two nuts 14' and 34 is formed of conducting material, and conveniently all three nuts are formed of conducting material. The first ap lied nut 14, abutting upon the; outer en `of sleeve 4, serves as a clamping member, -to secure the stem 11 in position, with the shoulder formed exteriorly upon it in firmengagement with the stepped bore of sleeve 4. A `ring 17 of conducting material,shaped -to serve as a is by the nut 34 A clamped to place against nut 14 vand between surfaoesso brought to contact electric union is completed.4 Whenthepartsare assembled the spaces withinthe 'structure `,areftilled withi insulating compound," applied in l liquid;`V condition. A filling hole such as has/"hitherto een employed, is indicated at 24, FigJ'I-.j y

It willbe vperceived in Fig'IthattheL-pro- 85 jections 3.are of considerable extentfan'd that the *sleeves 4f are prolonged withinfprojec.- tions 3, in' longpextending skirts 23. This skirted'extension of the insulatingsleeves is a feature of great practical importance.

betweenthe conductors 11 and the sleeve 4 is a cul-de-sac,` in which air may be trap ed,

'5 to the exclusion ofthe Hushing Hood ol insulatingl compound, proper filling is Jdifficult, and, lbut for my invention,vpracticnally impossible to attain. Neither inversion of the structure norl the exertion of pressure l upon the submergin Hood of compound will overcome the diHicu ty, tory practice.

My invention consists in providing a filland insure satisfac l ing'tube, extending longitudinally throughlv the lead-out structure, preferably in the form of a perforation through stem 11, longitudi` nally. Such a erforation is shown in the bore 25, extendlng from-the outer end of stem ,11. vThis perforation opens to the interior'of the ter'minal casing, and to that end it preferably. extends to a point at or immediately beyond the external shoulder upony stem 11, mentioned above. It there meets a cross bore 26,`which leads through the body of stem 1-1 and opens to the cylin# drical cavity'formed by and between conductor and skirted sleeve.

'A tube so placed may cooperate with al filling hole such as 24, Fig. I, and lconstitute an air escape, allowing the Hood of compound to advance'into the otherwise closed-ended cylindrical space between -conductor and sleeve. Again. the filling hole 24 may be dispensed with, and the tube may be made of such size as to allow both the introduction of compound to fill the whole space within the terminal casing and the coincident escape of air. Again, in a multiple-conductor in- .stallation, such as that shown in Fig. I, the fillinar hole 24 being dispensed with, the tube through one lead-out structure may constitute the filling hole and a Similar tube through another of the lead-out structures, or through both of the other lead-out structures, may constitute openings for air escape. Preferably, however, and particularly in a terminal for a single-conductor cable, where there is but one lead-out structure, I formv through the stem 11 two perforations, 25 and27, terminating, at the point already -indicated. in the cross-bores 26 and 28, as particularly shown in Figs. II and III. lOne of these, l preferably of larger size, 25, with double-opening crossfbore 26 is designed for the pouring-in of compound; the other, of

Filling is achieved before th cap-nut .18

. 6 N, 5 1s for the last time applied. The

pound' is introduced in obvious manner through perforation 25, while displaced air escapes through perforation 27, and the pouring'in of compound continues until the the perforations may be closed in any suit-V able manner. The cap nut 18 itself is shown to be chambered and I show it to be provided with an orifice filled by a plug 29. -The nut may be applied while the orifice is open, and if the operation of filling has not already been performed, it may be performed through such opening. Whether filling has been performed before or after the application of cap-nut 18, the space within the capnut itself is finally, filled.' Filling being completed, plug 29 is secured in place.

The chamber within the cap-nut filled with insulating compound, constitutes then a reservoir, and this reservoir may be enlarged indefinitely, or supplemented, and by means known to the art, the body of compound within `may be made effective, to maintain the'terminal at all times and under all conditions filled with compound, and to prevent under any circumstances the opening of spaces or fissures within the terminal.

The stem 11 is shown to be provided, additionally, with a bore 32, opening to the socket at the lower` end of'v stem 11, where i the end ofthe bared cable conductor is intrpduced. Cable conductors are, particularly 1n large cables. usually'stranded'; in some cases they are hollow. And insulating compound passing through this bore may fill more effectively spaces which. incidentally to installation, ma have developed in the conductor of the cab e itself.

I claim as my inventiom' 1. A -terminal structure for an electric 4cable includingla casing provided with an orifice for an incoming cable and with a second orifice for a lead-out structure a leadout structure adapted to beset in the lastnamed orifice, such lead-out structure including a sleeve `of insulating material with a stepped bore, and a shouldered stem of conducting material together with means for seating the stem in the bore of the sleeve with the shoulders in abutment, said stem being perforated by 'a duct penetrating the stem from its outer end and o enin through the stem laterally at points goth a ove and below the-shoulder aforesaid.

2. A. terminalv structure for an electric cable including a casing provided with an entice fer an incoming cable and with a seoond interiorly shouldered orifice for a end in a conductor-receiving socket, the stem lead-out structure, an exterorly shouldered being further provided With a longitudinal` lead-out structure adapted. to be set in the *perforation opening through the end of the i@ orifice last-named with the shoulders in abutstem and to Said socket.

6 ment, such lead-out structure including a In testimony whereof I have hereunto set sleeve of insulating material Aand a stem of my hand. conducting material terminating at its inner ATLEE B. SAURMAN. 

